1. Field of the Invention
The present invention relates to a microcomputer system utilizing a repeated reset operation to enter different operating modes, and the method to do the same.
2. Description of Related Art
Recently, various automation systems have been applied to everything from home utilities to factory equipment. These automation systems usually adopt either microcomputers or computer-controlled systems as the control center. In general, microcomputers or computer-controlled systems offer displays and keyboards to a user for monitoring and operating systems. In a microcomputer, self-detection or self-diagnosis programs are added in BIOS or in the form of packaged software applications, such as Scandisk and Norton. A computer technician can solve problems by pushing down a specific function key in a microcomputer to run these self-detection or self-diagnosis programs if the microcomputer is out of order.
However, for the purpose of simple structure and low cost, the system design for a microcomputer may omit the specific function key as mentioned above. Therefor, when the microcomputer is out of order, a computer technician has to solve the problem by using a dedicated self-diagnosis IC instead of the original one in the microcomputer. However, for a complicated mechanism such as a notebook computer, mounting and demounting an IC wastes time and manpower, and might damage the microcomputer.
Accordingly, to solve the problems of the prior art, it is an object of the present invention to provide a microcomputer system that utilizes a repeated reset operation to enter into different operating modes, and the method for doing the same. For a microcomputer system without a keyboard, the reset key on the microcomputer can be used to enter the microcomputer into the required operating mode; for example, to enter a self-diagnosis mode. By this way, it is not necessary to mount and demount an IC in the microcomputer when the microcomputer is out of order.
The microcomputer system according to the invention can be entered into different operating modes even if the microcomputer is not provided with a specific function key for doing so. Therefore, even microcomputers with keyboards can be simplified in terms of system configuration, thereby lowering the cost.
In the microcomputer system of the present invention, a general register or a memory will not clear its content during reset. Therefore, a specific value is written into an assigned register or memory a predetermined time after reset of the microcomputer system. If the microcomputer system is reset again during the predetermined time, the microcomputer will enter an operating mode according to the specific value. All the operating modes are stored in a predetermined program in the microcomputer. If the technician pushes the reset key again within the predetermined time after first reset operation, the microcomputer performs the corresponding self-diagnosis program and the results will be displayed on a display, thereby allowing the technician to repair or replace the elements of the microcomputer as necessary.
The present invention also provides a method utilizing repeated reset operations to enter different operating modes comprising the steps as follows:
First, when a microcomputer is started or manually reset, the program pre-programmed in the microcomputer will check the content of a specific address in the memory. The microcomputer will be set into an abnormal operating mode if a specific value indicating that a repeated reset has occurred is present in the specific address. The specific value indicating that a repeated reset has occurred will be written into the specific address if it is not already present. Then an echo message is outputted on the display. The microcomputer will repeat the first step if a reset occurs within a predetermined time. Alternately, the specific value will be cleared if the microcomputer system is not reset within the predetermined time, and echo message is cleared.
Next, check to see if an abnormal operating mode is set. If yes, the microcomputer enters the abnormal operating mode, otherwise the microcomputer enters the normal operating mode.
Therefore, the microcomputer will check to see whether or not a repeated reset has occurred before entering the normal mode, thereby determining whether or not to enter the abnormal mode. Accordingly, the repeated reset can be used to achieve the object of entering different operating modes.
The present invention can be applied to various microcomputer applications. For example, the microcomputer of a module testing board will display on the display whether an IC being tested is good or bad when a testing operator turns on the power and starts a particular testing signal source. If the technician wants to know which part of the IC is damaged or other characteristics of the ICs, the technician can simply push down the reset key twice within a predetermined delay time and enter the testing signal.